Yeah. I have them on my '68 Stepside. Original equipment. Listed on SPID. I love mine.
I think of them as Third World Radar. A cop can't sneak up on you from behind if you're watching your Six.
I added a big fish eye on the driver's side, and a smaller stick-on one on the passenger side, to flesh out the blind spots. Yes, you do have to keep the eyes moving for hidden things behind the mirrors. They are big. But that gives you superior resolution in veiwing to the rear.
They also create a lot of wind noise. As far as aerodynamic drag? Get real, It's a truck, you're probably hitting Terminal Velocity at 80 MPH anyway.
I'll have to hit Restart to post pix, so later on that.